Diagnostic performance of three-dimensional high-resolution anorectal manometry in identifying descending perineal...

Three-dimensional high-resolution anorectal manometry (3DHRAM) has been developed and introduced to explore pelvic floor disorder. The aim of this study was to evaluate the diagnostic performance of 3DHRAM in identifying descending perineal syndrome (DPS) in patients with obstructed defecation.

All consecutive patients referred in the previous 1 year for investigations of obstructed defecation were eligible. We included only patients who underwent both 3DHRAM and CD. Binary logistic regression was performed to identify independent predictors of DPS. The sensitivity, specificity, Youden index and area under ROC were calculated in order to propose a diagnostic strategy for DPS.

Thirty-eight patients (41.3%) presented with DPS on CD. Binary logistic regression analysis confirmed that perineal descent was independently associated with DPS (odds ratio = 1.13, 95% confidence interval 1.03-1.23, P = 0.009). On 3DHRAM, the excessive perineal descent parameter indicated a sensitivity of 0.61, a specificity of 0.76 with a Youden index of 0.37, and derived a cut-off value of 10.5 mm and achieved an area under the curve of 0.72. Perineal descent combined with rectocele, rectal mucosal prolapse, and dyssynergic pattern derived the best Youden Index (0.44) with a specificity of 0.89 and a sensitivity of 0.55.

This study suggests that 3DHRAM has potential as a complementary tool for diagnosing DPS at present. Future multi-center, prospective studies with larger, more diverse cohorts are needed to validate our findings and to better define the role of 3DHRAM in diagnosing DPS.